Improved battery cell terminal welding structure

Abstract

The utility model relates to an improved battery core terminal welding structure which comprises a terminal body welded with a battery core body and a plurality of welding spots arranged on the terminal body, and the terminal body is welded with the battery core body through the welding spots; a welding part is arranged on the terminal body; the welding part comprises a first welding area and a plurality of second welding areas, the first welding area is of an annular structure or a polygonal structure and is located in the center of the terminal body, and welding spots of the first welding area are uniformly distributed; according to the utility model, the core electron transmission capability of the battery core is improved, the dynamic performance of the corresponding part of the battery core is promoted, the capacity retention ratio of the battery core is obviously improved, and the uniformity of the long battery core in the charging process is improved, so that the problem that the stress of the core part is relatively large is solved, and the cycle life of the battery core is prolonged; the lithium ion battery has the advantages of improving the transmission capability, improving the capacity retention ratio of the battery core, improving the uniformity and prolonging the cycle life.

Description

Technical Field

[0001] The utility model belongs to the technical field of secondary battery production, and in particular relates to an improved battery cell terminal welding structure. Background Art

[0002] A secondary battery (rechargeable battery), also known as a rechargeable battery or storage battery, refers to a battery that can be used to activate the active material after the battery is discharged by charging. A new battery can be formed by using the reversibility of chemical reactions, that is, after a chemical reaction is converted into electrical energy, the chemical system can be repaired by electrical energy, and then converted into electrical energy by chemical reactions again, so it is called a secondary battery (rechargeable battery). The battery cell is the storage part of the secondary battery, which refers to a single electrochemical battery cell containing positive and negative electrodes. It is generally not used directly, unlike the battery containing a protection circuit and a shell, which can be used directly. At present, large cylindrical batteries are more widely used, but the large cylindrical batteries have an increased electrode length due to the increase in diameter, and the conventional welding scheme of connecting the positive and negative terminals by simple short-line welding cannot solve the problem of large electrode stress in the core due to the increase in electrode length, and poor electrode charge and discharge uniformity, which leads to a faster decay of the battery cycle life. Therefore, it is very necessary to provide an improved battery terminal welding structure that improves transmission capacity, improves battery capacity retention rate, improves uniformity, and improves cycle life. Summary of the invention

[0003] The purpose of the utility model is to overcome the deficiencies of the prior art and to provide an improved battery terminal welding structure that improves transmission capacity, improves battery capacity retention rate, improves uniformity, and improves cycle life.

[0004] The purpose of the utility model is achieved as follows: an improved battery terminal welding structure, which includes a terminal body welded to the battery body and a plurality of welding points arranged on the terminal body, the terminal body is welded to the battery body through the welding points; a welding portion is provided on the terminal body;

[0005] The welding portion includes a first welding area and a plurality of second welding areas. The first welding area is a ring-shaped structure or a polygonal structure and is located at the center of the terminal body. The welding points of the first welding area are evenly distributed.

[0006] The welding spots on the second welding area are evenly distributed.

[0007] The second welding area is a V-shaped structure, and the second welding area surrounds the first welding area.

[0008] The second welding area is a strip structure, and the second welding area surrounds the first welding area.

[0009] The first welding area is connected to the second welding area.

[0010] The beneficial effects of the utility model: the utility model is an improved battery cell terminal welding structure. During use, the utility model is based on the optimization adjustment of the positive and negative terminal welding schemes, and an additional circle of welding points is welded at the position opposite the center of the battery cell, thereby improving the core electron transmission capacity of the battery cell, promoting the dynamic performance of the corresponding parts of the battery cell, and significantly improving the battery cell capacity retention rate. The uniformity of the long battery cell during charging is improved, thereby improving the problem of large core stress and improving the cycle life of the battery cell. The utility model has the advantages of improving transmission capacity, improving battery cell capacity retention rate, improving uniformity, and improving cycle life. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a structural diagram of the positive electrode current collector in the prior art.

[0012] Figure 2 This is a structural diagram of the positive electrode current collector of the present utility model.

[0013] Figure 3 The structure diagram of the negative electrode current collector in the prior art.

[0014] Figure 4 It is a structural diagram of the negative electrode current collector of the utility model.

[0015] Figure 5 This is a cycle life diagram of the battery cell produced by the utility model.

[0016] In the figure: 1, positive electrode current collector; 2, first welding area; 3, second welding area; 4, welding point; 5, negative electrode current collector. Implementation

[0017] The utility model is further described below in conjunction with the accompanying drawings. Example

[0018] like Figure 2 As shown, an improved battery terminal welding structure includes a terminal body welded to the battery body and a plurality of welding points 4 arranged on the terminal body;

[0019] In this embodiment, the terminal body is a positive electrode current collector 1, and the positive electrode current collector 1 is welded to the battery cell body through a welding point 4; a welding portion is provided on the positive electrode current collector 1;

[0020] The welding portion includes a first welding area 2 and a plurality of second welding areas 3 . The first welding area 2 is a ring-shaped structure or a polygonal structure and is located at the center of the positive electrode current collector 1 . The welding points of the first welding area 2 are evenly distributed.

[0021] The welding spots on the second welding area 3 are evenly distributed.

[0022] The second welding area 3 is a V-shaped structure, and the second welding area 3 surrounds the first welding area 2 .

[0023] The utility model is an improved battery cell terminal welding structure. During use, the utility model is based on the optimization adjustment of the positive and negative terminal welding schemes, and an additional circle of welding points is welded at the position opposite to the center of the battery cell, thereby improving the core electron transmission capacity of the battery cell, promoting the dynamic performance of the corresponding parts of the battery cell, and significantly improving the battery cell capacity retention rate. The uniformity of the long battery cell during charging is improved, thereby improving the problem of large core stress and improving the cycle life of the battery cell. The utility model has the advantages of improving the transmission capacity, improving the battery cell capacity retention rate, improving the uniformity, and improving the cycle life. Example

[0024] like Figure 4 As shown, an improved battery terminal welding structure includes a terminal body welded to the battery body and a plurality of welding points 4 arranged on the terminal body;

[0025] In this embodiment, the terminal body is a negative electrode current collector 5, and the negative electrode current collector 5 is welded to the battery cell body through a welding point 4; a welding portion is provided on the negative electrode current collector 5;

[0026] The welding portion includes a first welding area 2 and a plurality of second welding areas 3 . The first welding area 2 is a ring-shaped structure or a polygonal structure and is located at the center of the positive electrode current collector 1 . The welding points of the first welding area 2 are evenly distributed.

[0027] The welding spots on the second welding area 3 are evenly distributed.

[0028] The second welding area 3 is a strip structure, and the second welding area 3 surrounds the first welding area 2 .

[0029] The first welding area 2 and the second welding area 3 are connected to each other.

[0030] In this embodiment, if Figure 5 As shown, after the positive electrode current collector 1 produced in Example 1 and the negative electrode current collector 5 produced in Example 2 were welded with the battery cell to form a battery, the capacity retention rate during the battery cycle was 1.5%@1000 weeks and 2.23%@1400 weeks higher than that of the control group (i.e., the prior art), and the capacity retention rate was significantly improved; the capacity decayed to 85%, the number of cycles increased by 228 weeks, and the cycle life increased by 16.3%; the battery cell cycle capacity was significantly improved.

[0031] The utility model is an improved battery cell terminal welding structure. During use, the utility model is based on the optimization adjustment of the positive and negative terminal welding schemes, and an additional circle of welding points is welded at the position opposite to the center of the battery cell, thereby improving the core electron transmission capacity of the battery cell, promoting the dynamic performance of the corresponding parts of the battery cell, and significantly improving the battery cell capacity retention rate. The uniformity of the long battery cell during charging is improved, thereby improving the problem of large core stress and improving the cycle life of the battery cell. The utility model has the advantages of improving the transmission capacity, improving the battery cell capacity retention rate, improving the uniformity, and improving the cycle life.

[0032] For example, Figure 1 , Figure 3 Shown are a structural diagram of a positive electrode current collector in the prior art and a structural diagram of a negative electrode current collector in the prior art respectively;

[0033] In the existing technical solution, the welding points 4 on the positive current collector 1 and the negative current collector 5 are only distributed on the second welding area 3. Since the battery body of the large cylindrical battery cell is relatively long, after the positive current collector 1 and the negative current collector 5 are welded to the battery body using this welding method, the core electrode stress of the battery body is large, the charging and discharging uniformity of the battery cell is poor, and the cycle life of the battery cell decays rapidly.

Claims

1. An improved battery terminal welding structure, characterized in that: It comprises a terminal body welded to the battery body and a plurality of welding points arranged on the terminal body, the terminal body is welded to the battery body through the welding points; a welding part is provided on the terminal body; The welding portion includes a first welding area and a plurality of second welding areas. The first welding area is a ring-shaped structure or a polygonal structure and is located at the center of the terminal body. The welding points of the first welding area are evenly distributed.

2. The improved battery terminal welding structure according to claim 1, characterized in that: The welding spots on the second welding area are evenly distributed.

3. The improved battery terminal welding structure according to claim 2, characterized in that: The second welding area is a V-shaped structure, and the second welding area surrounds the first welding area.

4. The improved battery terminal welding structure according to claim 2, characterized in that: The second welding area is a strip structure, and the second welding area surrounds the first welding area.

5. The improved battery terminal welding structure according to claim 4, characterized in that: The first welding area is connected to the second welding area.

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